128 research outputs found
Impact of dislocations and dangling bond defects on the electrical performance of crystalline silicon thin films
A wide variety of liquid and solid phase crystallized silicon films are
investigated in order to determine the performance limiting defect types in
crystalline silicon thin-film solar cells. Complementary characterization
methods, such as electron spin resonance, photoluminescence, and electron
microscopy, yield the densities of dangling bond defects and dislocations
which are correlated with the electronic material quality in terms of solar
cell open circuit voltage. The results indicate that the strongly differing
performance of small-grained solid and large-grain liquid phase crystallized
silicon can be explained by intra-grain defects like dislocations rather than
grain boundary dangling bonds. A numerical model is developed containing both
defect types, dislocations and dangling bonds, describing the experimental
results
Data-based modeling of drug penetration relates human skin barrier function to the interplay of diffusivity and free-energy profiles
Based on experimental concentration depth profiles of the antiinflammatory drug dexamethasone in human skin, we model the time-dependent drug penetration by the 1D general diffusion equation that accounts for spatial variations in the diffusivity and free energy. For this, we numerically invert the diffusion equation and thereby obtain the diffusivity and the free-energy profiles of the drug as a function of skin depth without further model assumptions. As the only input, drug concentration profiles derived from X-ray microscopy at three consecutive times are used. For dexamethasone, skin barrier function is shown to rely on the combination of a substantially reduced drug diffusivity in the stratum corneum (the outermost epidermal layer), dominant at short times, and a pronounced free-energy barrier at the transition from the epidermis to the dermis underneath, which determines the drug distribution in the long-time limit. Our modeling approach, which is generally applicable to all kinds of barriers and diffusors, allows us to disentangle diffusivity from free-energetic effects. Thereby we can predict short-time drug penetration, where experimental measurements are not feasible, as well as long-time permeation, where ex vivo samples deteriorate, and thus span the entire timescales of biological barrier functioning
Is It Rational to Assume that Infants Imitate Rationally? A Theoretical Analysis and Critique
It has been suggested that preverbal infants evaluate the efficiency of others' actions (by applying a principle of rational action) and that they imitate others' actions rationally. The present contribution presents a conceptual analysis of the claim that preverbal infants imitate rationally. It shows that this ability rests on at least three assumptions: that infants are able to perceive others' action capabilities, that infants reason about and conceptually represent their own bodies, and that infants are able to think counterfactually. It is argued that none of these three abilities is in place during infancy. Furthermore, it is shown that the idea of a principle of rational action suffers from two fallacies. As a consequence, is it suggested that it is not rational to assume that infants imitate rationally. Copyright (C) 2012 S. Karger AG, Base
An observational cohort study of the use of five-grass-pollen extract sublingual immunotherapy during the 2015 pollen season in France
Background:Allergic rhinitis affects around one quarter of the Western European population. Prophylactic allergen immunotherapy may be useful to reduce the risk of acute symptomatic attacks (hayfever). A five-grass pollen extract sublingual immunotherapy (5GPE-SLIT) has been developed for the treatment of allergic rhinitis to grass pollen. The objective of this study was to describe real-world treatment patterns with 5GPE-SLIT in France with respect to the prescribing information.Methods:This prospective cohort study was conducted by 90 community and hospital allergists. Adults and children (>â5 years old) starting a first treatment with 5GPE-SLIT prior to the 2015 pollen season were eligible. Data was collected at the inclusion visit and at the end of the pollen season. The primary outcome variable was compatibility of 5GPE-SLIT prescription with the prescribing information. This was determined with respect to four variables: (1) interval between 5GPE-SLIT initiation and onset of the pollen seasonââ„â3 months, (2) age of patientââ„â5 years, (3) intermittent symptoms or mild symptom severity (4) confirmatory diagnostic test. At study end, symptoms reported during the pollen season and any modifications to treatment or adverse events were documented.Results:280 adults and 203 children were enrolled. The prescribing information was respected for 82.5% of adults and 86.7% of children. A skin test was performed for all patients. 5GPE-SLIT was started 3-5 months before the pollen season for 85.3%. Treatment was discontinued before the start of the pollen season in 11.0% of patients overall, generally because of an adverse event (78.8% of discontinuations). The mean duration of treatment was 5.2 months in adults and 5.6 months in children. At the end of follow-up, symptoms during the pollen season were intermittent for 75.0% of adults and 85.7% of children, and severity was mild for 61.8 and 66.0% respectively. During 5GPE-SLIT, the following symptoms reported during the previous year were not reported again inâ>â50% of patients: nasal congestion, rhinorrhoea, repeated sneezing, conjunctivitis and nasal pruritus.Conclusions:5GPE-SLIT use was generally consistent with prescribing recommendations and was associated with an improvement of AR severity, with resolution of the principal AR symptoms in around half the patients treated.Trial registration EUPAS9358. Registered 13 May 2015. Not prospectively registered. http://www.encepp.eu/encepp/viewResource.htm?id=16229
Eozinofilna upala u alergijskom rinitisu i nosnoj polipozi
On histopathological examination, nasal polyps and nasal mucosa in allergic rhinitis show different forms of pseudostratified respiratory epithelium, whereas the dominant characteristic of lamina propria is an eosinophilic infiltration. The aim of this study was to compare interleukin (IL)-5 and eosinophilic cationic protein (ECP) levels in the nasal fluid of 42 patients: 12 with allergic rhinitis and nasal septal deviation, 17 non-atopic patients with nasal polyposis, and 13 atopic nasal polyp patients were enrolled in this cross-sectional study. Nasal secretion samples were collected a few days before surgery. The levels of IL-5 were measured using fl ow cytometry and the ECP using a commercial ELISA kit. In addition, we counted eosinophils in hematoxylin-and-eosin-stained sections of all nasal polyp and all nasal mucosa samples taken from the inferior nasal turbinates during septoplasty. A significantly higher concentration of IL-5 was found in the nasal fluid of atopic patients with nasal polyposis than in non-atopic nasal polyp patients (p=0.025) and patients with allergic rhinitis (p=0.05). ECP was higher in atopic nasal polyp patients than in patients with allergic rhinitis (p<0.0001) and than in non-atopic nasal polyp patients (p<0.0001). Polyp eosinophils were higher in atopicâ than in non-atopic patients (p<0.0001) and higher than in the mucosa of patients with allergic rhinitis (p<0.0001). These however had signifi cantly more mucosal eosinophils than was found in the polyps of non-atopic patientsâ (p=0.025). ECP levels in nasal fl uid and eosinophil counts in tissue specimens correlated well in all three groups of patients. Our study has shown that atopic nasal polyp patients have a higher level of eosinophilic inflammation than non-atopic patients with nasal polyps and patients with allergic rhinitis.Na histopatoloĆĄkim pregledima nosni polipi, kao i nosna sluznica u alergijskom rinitisu pokazuju razliÄite oblike pseudoslojevitog respiracijskog epitela, dok je osnovna karakteristika lamine proprije infiltracija eozinofilima. Cilj ove studije bio je usporediti koncentracije interleukina 5 (IL-5) i eozinofilnoga kationskog proteina (ECP) u nosnome sekretu pacijenata s alergijskim rinitisom, neatopiÄnih i atopiÄnih pacijenata s nosnom polipozom, kao i usporediti broj eozinofi la u tkivu nosnih polipa/nosne sluznice ovih pacijenata. Äetrdeset dvoje (n=42) pacijenata, 12-ero s alergijskim rinitisom i devijacijom nosnog septuma, 17-ero neatopiÄnih pacijenata s nosnom polipozom i 13-ero atopiÄnih pacijenata s nosnom polipozom bilo je ukljuÄeno u ovu presjeÄnu studiju. Uzorci nosnog sekreta bili su skupljeni iz nosnih ĆĄupljina svih ispitanika nekoliko dana prije kirurĆĄkog lijeÄenja. Koncentracije IL-5 mjerene su metodom protoÄne citometrije, dok su koncentracije ECP mjerene komercijalnim ELISA-kitom. Eozinofi li su brojeni u svim uzorcima tkiva nosnih polipa, kao i u svim uzorcima tkiva sluznice uzetih s donje nosne ĆĄkoljke tijekom septoplastike. ZnaÄajno viĆĄe koncentracije IL-5 izmjerene su u nosnom sekretu atopiÄnih pacijenata s nosnom polipozom u usporedbi s neatopiÄnim pacijentima s nosnom polipozom (p=0,025) i pacijentima s alergijskim rinitisom (p=0,05). NaĆĄi su rezultati pokazali viĆĄe koncentracije ECP u atopiÄnih pacijenata s nosnom polipozom nego u pacijenata s alergijskim rinitisom (p<0,0001) i u usporedbi s nealergiÄnim pacijentima s nosnom polipozom (p<0,0001). VeÄi broj eozinofi la izbrojen je u tkivu polipa atopiÄnih pacijenata nego u tkivu polipa neatopiÄnih pacijenata (p<0,0001), kao i u sluznici pacijenata s alergijskim rinitisom (p<0,0001). U nosnoj sluznici pacijenata s alergijskim rinitisom naĆĄli smo znaÄajno veÄi broj eozinofila nego u polipima neatopiÄnih pacijenata s nosnim polipima (p=0,025). KonaÄno, naĆĄli smo pozitivnu korelaciju izmeÄu nivoa ECP u nosnom sekretu i broja eozinofila u uzorcima tkiva u sve tri skupine ispitanika. ZakljuÄili smo da atopiÄni pacijenti s nosnom polipozom imaju viĆĄi stupanj eozinofilne upale u usporedbi s neatopiÄnim pacijentima s nosnim polipima i s pacijentima s alergijskim rinitisom
Run Away or Stick Together? The Impact of Organization-Specific Adverse Events on Alliance Partner Defection
Alliances are inter-organizational relationships wherein partners agree to engage in joint action and share benefits and burdens. But when might an adverse event that strikes one partner become too burdensome for another partner? Extant theories of alliance instability provide incomplete answers, which is problematic: for stricken organizations, anticipating whether their non-stricken partners will remain in the alliance can be essential for survival. Integrating insights from alliance dynamics and organizational stigma literatures, we theorize how an organization-specific adverse event affects a non-stricken partner's decision to continue with or defect from an alliance by considering factors that shift the balance between cohesive and disruptive forces. We propose that high stigmatization risk will increase the probability of partner defection through two disruptive mechanisms: relational uncertainty and stigma anxiety. Building on the idea that the same factors contributing to alliance formation may also condition partner defection, we theorize about the roles of partner resource interdependencies, relational embeddedness, and perceived partner similarity in amplifying or attenuating disruptive mechanisms triggered by an adverse event. We extend the research on partner defection and alliance instability by advancing an event-based view of alliance instability and specifying the conditions under which an alliance partner might defect
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
The Control of Instrumental Action Following Outcome Devaluation in Young Children Aged Between 1 and 4 Years
To determine the role of actionâoutcome learning in the control of young childrenâs instrumental behavior, the authors trained 18- to 48-month-olds to manipulate visual icons on a touch-sensitive display to obtain different types of video clips as outcomes. Subsequently, one of the outcomes was devalued by repeated exposure, and childrenâs propensity to perform the trained actions was tested in extinction. On test, children with a mean age greater than 2.5 years performed the action trained with the devalued outcome less than those trained with the still-valued outcome, thereby demonstrating that their actions were mediated by actionâoutcome learning. By contrast, the instrumental responses of younger children (mean age ïżœ2 years) were resistant to outcome devaluation and may have been elicited directly by the icons associated with each response, rather than mediated by a specific actionâoutcome expectation
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